javascript summarizes 20 ways to create functions

At work, it is common to create a function to solve a requirement problem. Here are 20 ways to create a function at work. How much do you know?

function sayHello(){
    console.log('hello');
}
function leave(){
    console.log('goodbye');
}
//test
sayHello();

Declare a function to complete the requirements

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

Everything you ask for, function expression number to solve

 
var Action = {
    sayHello : function(){
        console.log('hello');
    },
    leave : function(){
        console.log('goodbye');
    }
}
//test
Action.sayHello();

Creating a method object class looks cleaner

 
var Action = function(){};
Action.sayHello = function(){
    console.log('hello');
}
Action.leave = function(){
    console.log('goodbye');
}
//test
Action.sayHello();

Cleans up the namespace by adding attribute methods to the singleton

 
var Action = function(){
    return {
        sayHello : function(){
            console.log('hello');
        },
        leave : function(){
            console.log('goodbye');
        }
    }
}
// //test
var a = Action();
a.leave();

There's a lot more we can do to return the new object

 
var Action = function(){};
Action.prototype.sayHello = function(){
    console.log('hello');
}
Action.prototype.leave = function(){
    console.log('goodbye');
}
//test
var a = new Action();
a.sayHello();

Prototype chain points prevent multiple creation

 
var Action = function(){};
Action.prototype = {
    sayHello : function(){
        console.log('hello');
    },
    leave : function(){
        console.log('goodbye');
    }
}
//test
var a = new Action();
a.leave();

Objects give the prototype a cleaner look

 
var Action = function(){
    this.sayHello = function(){
        console.log('hello');
    }
    this.leave = function(){
        console.log('goodbye');
    }
}
//test
var a = new Action();
a.leave();

Don't forget to also add properties inside the class

 
Function.prototype.sayHello = function(){
    console.log('hello');
}
Function.prototype.leave = function(){
    console.log('leave');
}
//test
var f = function(){};
f.sayHello();

Base class prototype expansion, new 1 slice space

 
Function.prototype.addMethod = function(name, fn){
    this[name] = fn;
}
var methods = function(){};
methods.addMethod('sayHello', function(){
    console.log('hello');
});
methods.addMethod('leave', function(){
    console.log('leave');
});
//test
methods.sayHello();

Generically defined method functions are easier to use

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

0

We can also use classes for primitive assignment

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

1

Why not chain operation

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

2

Prototype + chain = 1 step further

 
Function.prototype.addMethod = function(obj){
    for(var key in obj){
        this[key] = obj[key];
    }
}
var methods = function(){};
methods.addMethod({
    sayHello : function(){
        console.log('hello');
    },
    leave : function(){
        console.log('goodbye');
    }
});
//test
methods.leave();

Adding objects does more once

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

4

What's wrong with a prototype

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

5

Adding objects functionally can also be chained

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

6

Class chain operations can also do more

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

7

Function added under encapsulation 1

 
Function.prototype.addMethod = function(){
    if(arguments.length < 1)
        return;
    var tostring = Object.prototype.toString;
    if(tostring.call(arguments[0]) === '[object Object]'){
        for(var key in arguments[0]){
            this.prototype[key] = arguments[0][key];
        }
    }else if(typeof arguments[0] === "string" && tostring.call(arguments[1]) === '[object Function]'){
        this.prototype[arguments[0]] = arguments[1];
    }
    return this;
}

Class addition is about personalization

 
var sayHello = function(){
    console.log('hello');
}
var leave = function(){
    console.log('goodbye');
}
//test
leave();

9

Go for personality.Don't say why

This is the end of this article, I hope you enjoy it.